unity Display.displays[].setParams Problem

I need to change the resolution of my 2nd Display screen. but with this script. it creates some kind of weird after shadow (just like windows xp file broswer lag...LOL check out the picture)

and this is my demo. I've already change the width and height to 1000 and 500 respectively

this is my script

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 public class DisplayScript : MonoBehaviour {
 
     // Use this for initialization
 
    public int width;
     public int height;
     public InputField widthInput;
     public InputField heightInput;
 
 
    public void changeResolution()
     {
         width = int.Parse(widthInput.text);
         height = int.Parse(heightInput.text);
         // Screen.SetResolution(width, height, false);
          Display.displays[1].SetParams(width, height,1,1);
     }
     
 
     
     void Start () 
     {
         for (int i = 0; i < Display.displays.Length; i++) 
            {
                Display.displays [i].Activate();
            }
 
     }
 }
 

notice the //Screen.SetResolution(width, height, false); its a great method as well, I actually prefer it but the problem is this will only change the resolution to my main interface(display 1) not the graphics part(display 2) I don't know how to call display 2 so I could use that that setScreenResolution only for Display 2